During the interwar period, aircraft and tank technologies matured and were combined with systematic application of the traditional German tactics of deep penetration and bypassing of enemy strong points to encircle and destroy enemy force in a Kesselschlacht (cauldron battle).[8][9] When Germany invaded Poland in 1939, Western journalists adopted the term blitzkrieg to describe this form of armoured warfare.[10] However, the term had already made an appearance as early as 1935, in a German military periodical Deutsche Wehr (German Defense), in connection to quick or lightning warfare.[5] Blitzkrieg operations were very effective during the campaigns of 1939–1941, and by 1940 the term had gained extensive use in Western media and journalism.[4][11] The blitzkrieg operations capitalized on surprise penetrations (e.g., the penetration of the Ardennes forest region), general enemy unpreparedness, and an inability to react swiftly enough to the attacker's offensive operations. During the Battle of France, the French, who made attempts to re-form defensive lines along rivers, were constantly frustrated when German forces arrived there first and pressed on.[11]

Many modern historians have come to the conclusion that blitzkrieg itself was never an official doctrine or concept of the Wehrmacht, and that it is a myth that it was officially adopted.[Notes 2] Some senior officers of the Wehrmacht, including Kurt Student, Franz Halder and Johann Adolf von Kielmansegg, disputed the idea that the blitzkrieg was an organized military concept of the Wehrmacht, and instead asserted that what many regarded as the blitzkrieg was nothing more than "ad hoc solutions that simply popped out of the prevailing situation" (Johann Adolf von Kielmansegg) and ideas that "naturally emerged from the existing circumstances" (Kurt Student) as a response to operational challenges.[19] German historian Frieser summarized the blitzkrieg as simply the result of German commanders blending the latest technology in the most beneficial way with the traditional military principles and "[employing] the right units in the right place at the right time" on the operational level of warfare, and that it was in no way a brand-new military doctrine or concept.[20] As such, many modern historians now understand the blitzkrieg as the outcome of the rejuvenation of the traditional German military principles, methods and doctrines of the 19th century with the latest weapon systems of the interwar period.[17]

However, many modern historians continue to use the term casually to describe the style of maneuver warfare practised by the Axis powers (particularly Germany) of this period, even though it was never a formal doctrine.[Notes 3] This is justifiable, since in the context of Guderian's[Notes 4] ideas of highly mobile formations in combined arms, the term blitzkrieg is extensively used as a synonym for maneuver warfare on the operational level.[31]

The classic interpretation of blitzkrieg is that of German tactical and operational methodology in the first half of the Second World War that was often hailed as a new method of warfare. The word, meaning "lightning war", in its strategic means is associated with a series of quick and decisive short battles to deliver a knockout blow to an enemy state before it could fully mobilize. The tactical meaning of blitzkrieg involves a coordinated military effort by tanks, mobilized infantry, artillery and aircraft, to create an overwhelming local superiority in combat power, to overwhelm an enemy and break through its lines.[32][33] Blitzkrieg as used by Germany had considerable psychological, or as some writers call, "terror" elements,[Notes 5] such as the 'Jericho Trompete', a noise-making siren on the Junkers Ju 87 dive-bomber to affect the morale of enemy forces.[Notes 6] The devices were largely removed when the enemy became used to the noise after the Battle of France in 1940, and instead bombs sometimes had whistles attached.[38][39] It is also common for historians and writers to include psychological tactics behind the line using Fifth columnists to spread rumours and lies among the civilian population in the theatre of operation.[32]

The origins of the term blitzkrieg are obscure. It was never used in the title of a military doctrine or handbook of the German army or air force.[40] It seems rarely to have been used in the German military press before 1939. Recent research conducted at the German military historical institute at Freiburg has found only two military articles from the 1930s in which it is employed. Neither article advocates any radically new military doctrine or approach to war. Both use the term simply to mean a swift strategic knockout. The first, published in 1935, deals primarily with food (and to a lesser extent with raw material) supplies in wartime. The term blitzkrieg is here employed with reference to Germany's efforts to win a quick victory in the First World War and is not associated with the use of armoured or mechanised forces or with airpower. The argument is that Germany must develop self-sufficiency in food supplies because it might again prove impossible to deal a swift knockout to her enemies and a protracted total war might prove unavoidable. The second article, published in 1938, states that launching a swift strategic knockout has great attractions for Germany but appears to accept that such a knockout will be very difficult to achieve by land attack under modern conditions (especially in view of the existence of systems of fortification like the Maginot Line) unless an exceptionally high degree of surprise is achieved. The author vaguely suggests that a massive strategic air attack might hold out better prospects, but that topic is not explored in any detail.[41]

Another relatively early use of the term in a German-language work was in a book by Fritz Sternberg, a JewishMarxist political economist who was a refugee from the Third Reich. Entitled Die Deutsche Kriegsstärke (German War Strength), it was published in Paris in 1939. It had been preceded by an English-language edition of 1938 called Germany and a Lightning War. The German edition uses the term blitzkrieg. The book's argument is that Germany is not prepared economically for a long war but might win a lightning war. It does not treat in any detail operational and tactical matters, and does not suggest that the German armed forces have evolved a radically new operational method. It offers scant clues as to how German lightning victories might be won.[42]

Hitler, in a speech in November 1941, said "I have never used the word Blitzkrieg, because it is a very silly word",[43] and it seems even at the beginning of 1942 he dismissed it as 'Italian phraseology'[44]

During the First World War, on the Western front, the two sides had been locked in a trench war, where kill zones by overlapping fire of machine guns and barbed wire prevented either side from breaking through. The British introduced the tank as invulnerable to machine gun fire, and able to cross trenches and breach barbed wire, to lead men across the battlefield. The British had been able to penetrate German lines this way, but not enough tanks were made before the war ended. The Germans had therefore first-hand experience of the potential of tanks to change the battlefield. Where the armies of Allied countries were slow to deploy and study the tank in the inter-war years[citation needed], the German military was very eager to study and master this new technology.[citation needed]

German operational theories began to evolve immediately after Germany's defeat in the First World War. The Treaty of Versailles limited any German Army to a maximum of 100,000 men, making impossible the deployment of massed troops which had characterized German strategy before the War. Although the German General Staff was also abolished by the treaty, it nevertheless continued to exist as the Truppenamt or "Troop Office", supposedly only an administrative body. Committees of veteran staff officers were formed within the Truppenamt to evaluate 57 issues of the war.[45] Their reports led to doctrinal and training publications, which became the standard procedures by the time of the Second World War. The Reichswehr was influenced by its analysis of pre-war German military thought, in particular the infiltration tactics which at the end of the war had seen some breakthroughs in the Western Front's trench war, and the maneuver warfare which dominated the Eastern Front.

German military history had previously been influenced by Carl von Clausewitz, Alfred von Schlieffen and von Moltke the Elder, who were proponents of maneuver, mass, and envelopment. During and after the First World War, these concepts were further developed by generals, such as Oskar von Hutier and the 1920s Reichswehr. Hutier's version used light infantry to attempt to penetrate enemy weak points in order to bypass and isolate heavily defended positions in the front line. These Sturmtruppen ("storm troops") were not to become decisively engaged, but open holes in the defenders trench system for the larger infantry units to pour through with heavier weapons and follow-up with a great advantage when attacking the isolated enemy strong points. The Storm Troops were to make the path through the defenses. Other reinforcements would then enter these breaches, and the entire enemy line would shortly collapse. Unlike the typical long duration artillery preparation before and attack, the Hutier tactics adopted a very short artillery preparation with immediate infantry assault on a narrow area of front. The attacks relied heavily on speed and surprise rather than weight of numbers along a wider front. Hutier tactics were used with great success in the Operation Michael offensive of 1918, and can in part be credited with restoring the war of movement once the Allied trench system at the main points of German attack had been penetrated. Continual movement of the attack formations was the essence of their tactics. The German Army pushed on toward Paris, and got within 120 kilometers before supply problems, and Allied reinforcements finally halted the German advance.[46] Following the First World War, these concepts were modified by the Reichswehr. The German army Chief of Staff, Hans von Seeckt, moved doctrine away from what he argued was an excessive focus on encirclement towards one based on speed.[47]

Under his command, a modern update of the doctrinal system called Bewegungskrieg ("maneuver warfare") and its associated leadership system called Auftragstaktik ("mission tactics"; i.e., units are assigned missions; local commanders decide how to achieve those missions) was developed which was a critical advantage and a major reason for the success of blitzkrieg. This concept was abandoned in January 1942. The OKW believed it too risky to allow German Corps and Army Groups to be operated and commanded independently by one field commander.

The German leadership had also been criticized for failing to understand the technical advances of the First World War, having given tank production the lowest priority and having conducted no studies of the machine gun prior to that war.[48] In response, German officers attended technical schools during this period of rebuilding after the war. The infiltration tactics developed by the German Army during the First World War became the basis for later tactics. German infantry had advanced in small, decentralized groups which bypassed resistance in favour of advancing at weak points and attacking rear-area communications. This was aided by coordinated artillery and air bombardments, and followed by larger infantry forces with heavy guns, which destroyed centers of resistance. These concepts formed the basis of the Wehrmacht's tactics during the Second World War.

On the Eastern Front of World War I, where combat did not bog down into trench warfare, German and Russian armies fought a war of maneuver over thousands of miles, which gave the German leadership unique experience which the trench-bound Western Allies did not have.[49] Studies of operations in the East led to the conclusion that small and coordinated forces possessed more combat worth than large, uncoordinated forces.

During this period, all the war's major combatants developed mechanised force theories. However, the official doctrines of the Western Allies differed substantially from those of the Reichswehr. British, French, and American doctrines broadly favoured a more deliberate set-piece battle, using mechanised forces to maintain the impetus and momentum of an offensive. There was less emphasis on combined arms, deep penetration or concentration. In short, their philosophy was not too different from that which they had at the end of World War I. Although early Reichswehr periodicals contained many translated works from Allied sources, they were rarely adopted. Technical advances in foreign countries were, however, observed and used in part by the Weapons Office of the Reichswehr. Foreign doctrines are widely considered to have had little serious influence.[50]

The British Army's lessons were mainly drawn from the successful infantry and artillery offensives on the Western Front in late 1918. To obtain the best cooperation between all arms, emphasis was placed on detailed planning, rigid control, and adherence to orders.[51] Although mechanisation of the Army was considered as a means of avoiding the heavy casualties and indecisive nature of the offensives during the earlier years of the war, no strategic doctrine was evolved to match technical developments.[52]

However, the Sinai and Palestine Campaign had witnessed operations that involved some aspects of what would later be known as blitzkrieg.[53] Key elements in the "blitzkrieg warfare" at the decisive Battle of Megiddo included concentration, surprise and speed; success depended on attacking only in terrain favouring the movement of large formations around the battlefield and tactical improvements in the British artillery and infantry attack.[54][55] General Edmund Allenby used infantry to successfully attack the strong Ottoman front line in close coordination with supporting artillery,[56] augmented by the guns of two destroyers.[57] Through constant pressure by both infantry and cavalry, two Ottoman armies in the Judean Hills were kept off-balance and virtually encircled during the Battles of Sharon and Nablus which have become known as the Battle of Megiddo.[58]

These methods induced "strategic paralysis" among the defending Ottoman troops and led to their rapid and complete collapse.[59] In an advance of 65 miles (105 km), captures were estimated at "at least 25,000 prisoners and 260 guns."[60] Theorist Basil Liddell Hart considered that the most important aspect of the operation was the degree to which the Ottoman commanders were first denied intelligence on the British preparations for the attack through British air superiority, and second crippled by air attacks on their headquarters and telephone exchanges paralysing their attempts to react to the rapidly deteriorating situation.[53]

French doctrine in the mid-war years was defense-oriented. Colonel Charles de Gaulle was a known advocate of concentration of armor and airplanes. His opinions were expressed in his book Vers l'Armée de Métier (Towards the Professional Army). Like von Seeckt, he concluded that France could no longer maintain the huge armies of conscripts and reservists with which World War I had been fought, and he sought to use tanks, mechanised forces and aircraft to allow a smaller number of highly trained soldiers to have greater impact in battle. His views little endeared him to the French high command, but are claimed by some to have influenced Heinz Guderian.[61]

In 1916, General Alexei Brusilov had used infiltration tactics and surprise during the Brusilov Offensive. Later, Marshal Mikhail Tukhachevsky, one of the most prominent officers of the Red Army of the Soviet Union during the inter-war years, developed the concept of deep operations from his experiences of the Polish-Soviet War. These concepts would guide Red Army doctrine throughout World War II. Realising the limitations of infantry and cavalry, Tukhachevsky was an advocate of mechanised formations and the large-scale industrialization required. However, Robert Watt states that blitzkrieg holds little in common with Soviet deep battle.[62] H P Willmott has noted that deep battle contains two critical differences–it advocated the idea of total war, not limited operations, and it also rejected the idea of the decisive battle in favour of several large scale and simultaneous offensives.[63]

The Reichswehr and the Red Army collaborated in war games and tests in Kazan and Lipetsk beginning in 1926. Set within the Soviet Union, these two centers were used to field test aircraft and armoured vehicles up to the battalion level as well as house aerial and armoured warfare schools through which officers were rotated. This was done in the Soviet Union, in secret, to evade the Treaty of Versailles's occupational agent, the Inter-Allied Commission.[64]

After becoming head of government in 1933, Adolf Hitler ignored the Versailles Treaty provisions. A command for armoured forces was created within the German Wehrmacht: the Panzerwaffe, as it came to be known later. The Luftwaffe (the German air force) was established, and development began on ground-attack aircraft and doctrines. Hitler was a strong supporter of this new strategy. He read Guderian's book Achtung – Panzer! and upon observing armoured field exercises at Kummersdorf he remarked, "That is what I want — and that is what I will have."[65][66]

Heinz Guderian was probably the first to fully develop and advocate the principles associated with blitzkrieg. He summarized combined-arms tactics as the way to get the mobile and motorized armoured divisions to work together and support each other in order to achieve decisive success. In his book, Panzer Leader, he wrote:

In this year, 1929, I became convinced that tanks working on their own or in conjunction with infantry could never achieve decisive importance. My historical studies, the exercises carried out in England and our own experience with mock-ups had persuaded me that the tanks would never be able to produce their full effect until the other weapons on whose support they must inevitably rely were brought up to their standard of speed and of cross-country performance. In such formation of all arms, the tanks must play primary role, the other weapons beings subordinated to the requirements of the armour. It would be wrong to include tanks in infantry divisions; what was needed were armoured divisions which would include all the supporting arms needed to allow the tanks to fight with full effect.[67]

Guderian believed that developments in technology were required to support the theory; especially, equipping armoured divisions—tanks foremost–with wireless communications. Guderian insisted in 1933 to the high command that every tank in the German armoured force must be equipped with a radio.[68] At the start of the war, only the German army was thus prepared with all tanks "radio equipped". This proved critical in early tank battles where German tank commanders exploited the organizational advantage over the Allies that radio communication gave them. Later all Allied armies would copy this innovation.

German volunteers first used armour in live field conditions during the Spanish Civil War of 1936. Armour commitment consisted of Panzer Battalion 88, a force built around three companies of Panzer I tanks that functioned as a training cadre for Nationalists. The Luftwaffe deployed squadrons of fighters, dive bombers, and transport aircraft as the Condor Legion.[69] Guderian said that the tank deployment was "on too small a scale to allow accurate assessments to be made."[70] The true test of his "armoured idea" would have to wait for the Second World War. However, the Luftwaffe also provided volunteers to Spain to test both tactics and aircraft in combat, including the first combat use of the Stuka.

During the war, the Condor Legion undertook the bombing of Guernica which had a tremendous psychological effect on the populations of Europe. The results were exaggerated, and the Western Allies concluded that the "city-busting" techniques were now a part of the German way in war. The targets of the German aircraft were actually the rail lines and bridges. But lacking the ability to hit them with accuracy (only three or four Ju 87s saw action in Spain), a method of carpet bombing was chosen resulting in heavy civilian casualties.[71]

The Germans referred to a Schwerpunkt (focal point) and to a Schwerpunktprinzip (concentration principle) in the planning of operations. They viewed the Schwerpunkt as a center of gravity or point of maximum effort, where a decisive action could be achieved. Ground, mechanised and tactical air forces were concentrated at this point of maximum effort whenever possible. By local success at the Schwerpunkt, a small force achieved a breakthrough and gained advantages by fighting in the enemy's rear. Guderian summarized this doctrine as "Klotzen, nicht kleckern!"[72] (approx. "Get in there and do it! Don't mess about!").[73]

To achieve a breakthrough, armoured forces would attack the enemy's defensive line directly, supported by motorized infantry, artillery fire and aerial bombardment, in order to create a breach in the enemy's line. Through this breach, the tanks and motorised units could break through without the traditional encumbrance of the slow logistics of infantry on foot. In the opening phase of an operation, air forces sought to gain superiority over enemy air-forces by attacking aircraft on the ground, bombing their airfields, and seeking to destroy them in the air. The principle of Schwerpunkt enabled the attacker to win numerical superiority at the point of the main effort, which in turn gave the attacker tactical and operational superiority even though the attacker may be numerically and strategically inferior along the front overall.[74]

Having achieved a breakthrough of the enemy's line, units comprising the schwerpunkt were not supposed to become decisively engaged with enemy frontline units to the right and left of the breakthrough area. Units pouring through the hole were tasked to drive upon set objectives in the rear areas of the enemy front line. In World War II, German Panzer forces, for example, utilized motorized mobility, attempted to paralyze the enemy's ability to react. Moving faster than enemy forces, mobile forces exploited weaknesses and acted before opposing forces could formulate a response. Central to this is the decision cycle. Every decision made by German or opposing forces required time to gather information, make a decision, disseminate orders to subordinates, and then implement this decision through action. Through superior mobility and faster decision-making cycles, mobile forces could take action on a situation sooner than the forces opposing them. Directive control was a fast and flexible method of command. Rather than receiving an explicit order, a commander would be told of his superior's intent and the role which his unit was to fill in this concept. The exact method of execution was then a matter for the low-level commander to determine as best fit the situation. Staff burden was reduced at the top and spread among commands more knowledgeable about their own situation. In addition, the encouragement of initiative at all levels aided implementation. As a result, significant decisions could be effected quickly and either verbally or with written orders a few pages long.[75]

An operation's final phase, was the destruction of the pockets which were enveloped by the initial stages of an operation. The Kesselschlacht, ("cauldron battle"), was a concentric attack on encircled forces earlier bypassed by the Schwerpunkt attack(s). It was here that most losses were inflicted upon the enemy, primarily through the capture of prisoners and weapons. During Barbarossa, massive encirclements netted nearly 3,500,000 Soviet prisoners along with masses of equipment.[Notes 7][77]

In this regard, close air support was provided in the form of the dive bomber and medium bomber. They would support the focal point of attack from the air. German successes are closely related to the extent to which the German Luftwaffe was able to control the air war in early campaigns in Europe and the Soviet Union. However, the Luftwaffe was a broadly based force with no constricting central doctrine, other than its resources should be used generally to support national strategy. It was flexible and it was able to carry out both operational-tactical, and strategic bombing effectively. Flexibility was the Luftwaffe's strength in 1939–1941. Paradoxically, from that period onward it became its weakness. While Allied Air Forces were tied to the support of the Army, the Luftwaffe deployed its resources in a more general, operational way. It switched from air superiority missions, to medium-range interdiction, to strategic strikes, to close support duties depending on the need of the ground forces. In fact, far from it being a dedicated panzer spearhead arm, less than 15 percent of the Luftwaffe was designed for close support of the army in 1939.[78]

The concepts associated with the term blitzkrieg – deep penetrations by armour, large encirclements, and combined arms attacks – were largely dependent upon terrain and weather conditions. Where the ability for rapid movement across "tank country" was not possible, armoured penetrations were often avoided or resulted in failure. Terrain would ideally be flat, firm, unobstructed by natural barriers or fortifications, and interspersed with roads and railways. If it was instead hilly, wooded, marshy, or urban, armour would be vulnerable to infantry in close-quarters combat and unable to break out at full speed. Additionally, units could be halted by mud (thawing along the Eastern Front regularly slowed both sides) or extreme snow. Armour, motorised and aerial support was also naturally dependent on weather.[citation needed] It should however be noted that the disadvantages of such terrain could be nullified if surprise was achieved over the enemy by an attack through such terrain. During the Battle of France, the German blitzkrieg-style attack on France went through the Ardennes. There is little doubt that the hilly, heavily wooded Ardennes could have been relatively easily defended by the Allies, even against the bulk of the German armoured units. However, precisely because the French thought the Ardennes unsuitable for massive troop movement, particularly for tanks, they were left with only light defences which were quickly overrun by the Wehrmacht. The Germans quickly advanced through the forest, knocking down the trees the French thought would impede this tactic.[79]

Allied air superiority became a significant hindrance to German operations during the later years of the war. Early German successes were conducted when Allied aircraft could not make a significant impact on the battlefield or its air space. In addition, the Germans enjoyed air parity or superiority which allowed the unencumbered movement of ground forces, close air support and aerial reconnaissance.[80] By 1944, however, the Western Allies' fighter-bomber aircraft were so effective that German vehicle crews experienced great difficulty moving en masse during daylight.[81] Indeed, the final German offensive operation in the west, Operation Wacht am Rhein, was planned to take place during poor weather to minimize interference by Allied aircraft. Under these conditions it was difficult for German commanders to employ the "armoured idea" to its envisioned potential, if at all.[80]

Blitzkrieg is vulnerable to an enemy that is robust enough to weather the shock of the attack and that does not panic at the idea of enemy formations in its rear area. This is especially true if the attacking formation lacks the reserve to keep funneling forces into the spearhead, or lacks the mobility to provide infantry, artillery and supplies into the attack. If the defender can hold the shoulders of the breach they will have the opportunity to counterattack into the flank of the attacker, potentially cutting off the van as happened to Kampfgruppe Peiper in the Ardennes.

During the Battle of France in 1940, De Gaulle's4th Armoured Division and elements of the British Expeditionary Force's 1st Army Tank Brigade both made probing attacks on the German flank, actually pushing into the rear of the advancing armoured columns at times. This may have been a reason for Hitler to call a halt to the German advance. Those attacks combined with Maxime Weygand's Hedgehog tactic would become the major basis for responding to blitzkrieg attacks in the future: deployment in depth, permitting enemy or "shoulders" of a penetration was essential to channeling the enemy attack, and artillery, properly employed at the shoulders, could take a heavy toll of attackers. While Allied forces in 1940 lacked the experience to successfully develop these strategies, resulting in France's capitulation with heavy losses, they characterized later Allied operations. For example, at the Battle of Kursk the Red Army employed a combination of defense in great depth, extensive minefields, and tenacious defense of breakthrough shoulders. In this way they depleted German combat power even as German forces advanced.[citation needed] The reverse can be seen in the Russian summer offensive of 1944. German attempts to weather the storm and fight out of encirclements failed due to the Russians' ability to continue to feed armoured units into the attack, maintaining the mobility and strength of the offensive, arriving in force deep in the rear areas faster than the Germans could regroup and resulting in the devastating destruction of Army Group Center.

Although effective in quick campaigns against Poland and France, mobile operations could not be sustained by Germany in later years. Strategies based on maneuver have the inherent danger of the attacking force overextending its supply lines, and can be defeated by a determined foe who is willing and able to sacrifice territory for time in which to regroup and rearm, as the Soviets did on the Eastern Front (as opposed to, for example, the Dutch who had no territory to sacrifice). Tank and vehicle production was a constant problem for Germany; indeed, late in the war many panzer "divisions" had no more than a few dozen tanks.[82] As the end of the war approached, Germany also experienced critical shortages in fuel and ammunition stocks as a result of Anglo-American strategic bombing and blockade. Although production of Luftwaffe fighter aircraft continued, they would be unable to fly for lack of fuel. What fuel there was went to panzer divisions, and even then they were not able to operate normally. Of those Tiger tanks lost against the United States Army, nearly half of them were abandoned for lack of fuel.[83]

Despite the term blitzkrieg being coined by journalists during the Invasion of Poland of 1939, historians Mathew Cooper and J. P Harris generally hold that German operations during it were more consistent with more traditional methods. The Wehrmacht's strategy was more in line with Vernichtungsgedanken, or a focus on envelopment to create pockets in broad-front annihilation. Panzer forces were dispersed among the three German concentrations[84] without strong emphasis on independent use, being used to create or destroy close pockets of Polish forces and seize operational-depth terrain in support of the largely un-motorized infantry which followed.

While early German tanks, Stuka dive-bombers and concentrated forces were used in the Polish campaign, the majority of the battle was conventional infantry and artillery based warfare and most Luftwaffe action was independent of the ground campaign. Matthew Cooper wrote that

[t]hroughout the Polish Campaign, the employment of the mechanised units revealed the idea that they were intended solely to ease the advance and to support the activities of the infantry....Thus, any strategic exploitation of the armoured idea was still-born. The paralysis of command and the breakdown of morale were not made the ultimate aim of the ... German ground and air forces, and were only incidental by-products of the traditional maneuvers of rapid encirclement and of the supporting activities of the flying artillery of the Luftwaffe, both of which had as their purpose the physical destruction of the enemy troops. Such was the Vernichtungsgedanke of the Polish campaign.[85]

John Ellis explained that "...there is considerable justice in Matthew Cooper's assertion that the panzer divisions were not given the kind of strategic mission that was to characterize authentic armoured blitzkrieg, and were almost always closely subordinated to the various mass infantry armies."[86]

Steven Zaloga states: "Whilst Western accounts of the September campaign have stressed the shock value of the panzers and Stuka attacks, they have tended to underestimate the punishing effect of German artillery on Polish units. Mobile and available in significant quantity, artillery shattered as many units as any other branch of the Wehrmacht."[87]

The German invasion of France, with subsidiary attacks on Belgium and the Netherlands, consisted of two phases, Operation Yellow (Fall Gelb) and Operation Red (Fall Rot). Yellow opened with a feint conducted against the Netherlands and Belgium by two armoured corps and paratroopers. Most of the German armoured forces were placed in Panzer Group von Kleist, which attacked through the Ardennes, a lightly defended sector that the French planned to reinforce if need be before the Germans could bring up their heavy siege artillery.[88] As it turned out, there was no time for such a reinforcement to be sent, for the Germans did not wait for siege artillery, but reached the Meuse and achieved a breakthrough at the Battle of Sedan in three days time.[89]

The group raced to the English Channel, reaching the coast at Abbeville, thus cutting off the British Expeditionary Force, Belgian Army, and some divisions of the French Army in northern France. The armoured and motorized units under Guderian, Rommel and others advanced far beyond the following divisions, and indeed far in excess of that with which Hitler and the German high command was comfortable. When the Allies initiated a counterattack at Arras using the heavily armoured British Matilda tanks, a brief panic was created in the German High Command. The armoured and motorized forces were halted by Hitler outside the port city of Dunkirk, which was being used to evacuate the Allied forces. Hermann Göring promised the Luftwaffe would complete the destruction of the encircled armies, but aerial operations could not prevent the evacuation of the majority of the Allied troops. The operation, code named Operation Dynamo by the British, resulted in some 330,000 French and British troops being evacuated.[90]

Overall, Yellow succeeded beyond what anyone had expected, overcoming the Allies 4,000 armoured vehicles, vehicles which in many cases were superior to the German in armour and caliber of cannon.[91] However the French and British frequently used their tanks in the role of assisting the infantry, thus they were dispersed across many units. The German blitzkrieg method called for force to be concentrated at the point of attack, giving them the firepower to overcome the defenses.

German advances during the Battle of France

This left the French armies much reduced in strength and the confidence of their commanders shaken. With much of their own armour and heavy equipment lost in Northern France, they now lacked the resources to fight a mobile war. The German's followed their initial success with Operation Red, a triple-pronged offensive. The XV Panzer Corps attacked towards Brest, XIV Panzer Corps attacked east of Paris, towards Lyon, and Guderian's XIX Panzer Corps circled back, completing the encirclement of the French forces in the Maginot Line. The defending forces were hard pressed to organize any sort of counter-attack. They were continually ordered to form new defensive lines along the next river, but would arrive to find German forces had already passed the position and were moving deeper into the country. An armoured counter-attack organized by Colonel de Gaulle could not be sustained, and he had to retreat.

Prior to the German offensive in May, Winston Churchill had said "Thank God for the French Army".[92] That same French army collapsed after barely two months of fighting. This was in shocking contrast to the four years of trench warfare they had engaged in during the First World War. The French president of the Ministerial Council, Reynaud, attributed the collapse in a speech on 21 May 1940:

The truth is that our classic conception of the conduct of war has come up against a new conception. At the basis of this...there is not only the massive use of heavy armoured divisions or cooperation between them and airplanes, but the creation of disorder in the enemy's rear by means of parachute raids.

In fact, the German army had not used paratroop attacks in France. The one major paratrooper attack was used earlier in the Netherlands to capture a bridge and a number of small-scale glider-landings were conducted in Belgium to capture terrain dominating bottle-necks on planned routes of advance prior to the arrival of the main ground forces (the most renowned being the landing on the Belgian border-fort of Eben-Emael). The real cause for the fall of France was the blitzkrieg method of warfare.

After 1941–42, armoured formations were increasingly used as a mobile reserve against Allied breakthroughs. The black arrows depict armoured counter-attacks.

Use of armoured forces was crucial for both sides on the Eastern Front. Operation Barbarossa, the German invasion of the Soviet Union in 1941, involved a number of breakthroughs and encirclements by motorized forces. Its stated goal was "to destroy the Russian forces deployed in the West and to prevent their escape into the wide-open spaces of Russia."[93] A key factor was the surprise attack which included the near annihilation of the total Soviet airforce by simultaneous attacks on airfields. On the ground, four giant panzer armies encircled surprised and disorganized Soviet forces, followed by marching infantry which completed the encirclement and defeated the trapped forces. The first year of the Eastern Front offensive can generally be considered to have had the last successful major mobile operation for the German army.

After Germany's failure to destroy the Soviets before the winter of 1941, the strategic failure above the German tactical superiority became apparent. Although the German invasion successfully conquered large areas of Soviet territory, the overall strategic effects were more limited. The Red Army was able to shrug off enormous losses and regroup with new formations far to the rear of the main battle line, and eventually defeat the German forces for the first time in the Battle of Moscow.[94]

In the summer of 1942, when Germany launched another offensive in the southern USSR against Stalingrad and the Caucasus, the Soviets again lost tremendous amounts of territory, only to counter-attack once more during winter. German gains were ultimately limited by Hitler diverting forces from the attack on Stalingrad itself and seeking to pursue a drive to the Caucasus oilfields simultaneously as opposed to subsequently as the original plan had envisaged. Even so, the Wehrmacht was becoming overstretched. By winning operationally, strategically it could not keep up the momentum as the durability of the Soviet Union's manpower resources, industrial base and aid from the West began to take effect.[94]

In the summer of 1943 the Wehrmacht launched another combined forces offensive operation – Zitadelle (Citadel) – against the Soviet salient at Kursk. Soviet defensive tactics were by now hugely improved, particularly in terms of artillery and effective use of air support. Eventually, the Battle of Kursk marked the Soviet switch to offense and the revival of deep operations.[95] According to military historain David Glantz, for the first time the blitzkrieg was defeated in summer and the opposing forces were able to mount their own successful counteroperation.[95] During the preparation for the Battle of Kursk, the Soviet command had been apprised of German intentions through Ultra intercepts, and this time they trusted the information they were being given was valid, and not an elaborate British deception. At Kursk the Soviets were able to develop a very deep defensive front. In addition, Soviet defensive tactics, their use of artillery and their use of close air support were much improved. As the strength of the German forces began to wane, the battle was marked by the Soviet switch over to offense and their use of the revived doctrine of deep operations. Of course, the Kursk operation did not comprise a true "blitzkrieg" operation, although it was intended to be, as there was no element of surprise, no breakthrough to outflank or strike at rear areas, and no psychological pressure being exerted upon the minds of the Soviet command.

By the summer of 1944 the reversal of fortune was complete and Operation Bagration saw Soviet forces inflict crushing defeats on Germany through the aggressive use of armour, infantry and air power in combined strategic assault, known as deep operations.

As the war progressed, Allied armies began using combined arms formations and deep penetration strategies that Germany had used in the opening years of the war. Many Allied operations in the Western Desert and on the Eastern Front relied on massive concentrations of firepower to establish breakthroughs by fast-moving armoured units. These artillery-based tactics were also decisive in Western Front operations after Operation Overlord and both the British Commonwealth and American armies developed flexible and powerful systems for using artillery support. What the Soviets lacked in flexibility, they made up for in number of multiple rocket launchers, cannon and mortar tubes. The Germans never achieved the kind of fire concentrations their enemies were capable of by 1944.[96]

After the Allied landings at Normandy, Germany made attempts to overwhelm the landing force with armoured attacks, but these failed for lack of co-ordination and through Allied air superiority. The most notable attempt to use deep penetration operations in Normandy was at Mortain, which exacerbated the German position in the already-forming Falaise Pocket and assisted in the ultimate destruction of German forces in Normandy. The Mortain counter-attack was effectively destroyed by U.S. 12th Army Group with little effect on its own offensive operations.[97]

Germany's last offensive on its Western front, Operation Wacht am Rhein, was an offensive launched towards the vital port of Antwerp in December 1944. Launched in poor weather against a thinly held Allied sector, it achieved surprise and initial success as Allied air power was stymied by cloud cover. However, stubborn pockets of defence in key locations throughout the Ardennes, the lack of serviceable roads, and poor German logistics planning caused delays. Allied forces deployed to the flanks of the German penetration, and as soon as the skies cleared, Allied aircraft were again able to attack motorized columns. The stubborn defense by US units and German weakness led to a defeat for the Germans.[citation needed]

The origins of blitzkrieg are in some doubt: if it existed, who contributed to it, whether it was part of German war strategy in 1933 – 1939.

There has been a great deal of debate about whether blitzkrieg existed as a coherent military strategy. Many historians now hold the position that blitzkrieg was not a military theory, and the campaigns conducted by the German military in 1939 to circa, 1942 (with the exception of Operation Barbarossa) were improvised invasions put together and modified at the last moment and therefore was not a proper military strategy. In the past blitzkrieg has also been hailed as a Revolution in Military Affairs (RMA). In recent years a large number of writers and historians have come to the conclusion it was not a new form of warfare invented by the German military, but an old method of pursuing decisive battles using new technology.[98]

There is disagreement on whether Germany had designed its war plans around blitzkrieg. The popular view can be summarized in an essay published in 1965, the then Captain Robert O'Neill, Professor of the History of War at the Oxford University. Writing on Doctrine and Training in the German Army 1919–1939, O'Neill stated:

What makes this story worth telling is the development of one idea: the blitzkrieg. The German Army had a greater grasp of the effects of technology on the battlefield, and went on to develop a new form of warfare by which its rivals when it came to the test were hopelessly outclassed.

Some historians were prepared to go even further, claiming that blitzkrieg was not merely an operational doctrine of the German armed forces but a strategic concept on which the leadership of the Third Reich based its strategic and economic planning. Those who made the Third Reich's military plans and organized its war economy appear rarely, if ever, to have employed the term blitzkrieg in official documents. The idea that the German army operated on a "blitzkrieg doctrine" was vigorously attacked in the late 1970s by Matthew Cooper. The concept of a blitzkrieg Luftwaffe was challenged by Richard Overy in the late 1970s and by Williamson Murray in the mid-1980s. The thesis that the Third Reich went to war on the basis of "blitzkrieg economics" was criticized by Richard Overy in the 1980s and Historian George Raudzens highlighted the many, somewhat conflicting, senses in which historians have used the word. Though the notion of a German blitzkrieg concept or doctrine survive in popular consciousness and popular literature, and many professional historians also still support the thesis.[99]

Frieser, in agreement with Overy, Cooper and others that reject the existence of a blitzkrieg doctrine, argues that after the failure of the Schlieffen Plan in 1914, the German Army came to the conclusion decisive battles could not be executed on a strategic level. This meant the idea of one early large scale offensive could not bring about a knockout blow. Frieser argues that the OKW had intended to avoid the decisive battle concepts of its predecessors and planned for a long all out war of attrition. It was only after the hastily improvised plan for the invasion of Western Europe in 1940 and its successful conclusion, which led the German General Staff to believe that decisive battles were not obsolete. It was only after the Battle of France German thinking reverted to the possibility of a blitzkrieg method for the Balkan Campaign and Operation Barbarossa.[100]

The position of some academic literature regards the notion that the Third Reich developed a blitzkrieg strategy to achieve its total aims as a myth, and therefore such notion has been widely disputed.

Historians Shimon Naveh and Richard Overy reject the idea that blitzkrieg was a military doctrine.[101] Naveh states, "The striking feature of the blitzkrieg concept is the complete absence of a coherent theory which should have served as the general cognitive basis for the actual conduct of operations".[102] Naveh described it as an "ad hoc solution" to operational dangers, thrown together at the last moment.[103]

Richard Overy also rejected the idea that Hitler and the Nazi regime ever intended a blitzkrieg war. The suggestion that the German state intentionally streamlined its economy to carry out its grand strategy in a series of short campaigns in the near future was false.[104] In fact Hitler intended to start an unlimited war, at a much later date than 1939. But the Third Reich'sforeign policy had forced the Nazi state into war before it had fully prepared.[105] Hitler's, and the Wehrmacht's planning attitudes during the 1930s do not reflect a blitzkrieg method, but the exact opposite.[106]

Historian J. P Harris has pointed out that the Germans never used the word blitzkrieg. It was never used in any German military field manual, either in the Army or the Air Force. It first appeared in September 1939, by a Times newspaper reporter. Harris also rejects that German military thinking developed any kind of blitzkrieg mentality.[107]

The German armament industry did not fully mobilize until 1944, and this has led to some historians in the 1960s, particularly Alan Milward, to develop a theory of blitzkrieg economics. Milward argued the German Reich could not fight a long war, so it deliberately refrained from arming in depth, to arming in breadth, to enable it to win a series of quick victories. Milward alleged an economy positioned between a full war economy and a peacetime economy.[110][111][112] The purpose of the blitzkrieg economy was to allow the German people to enjoy high living standards in the event of hostilities, and avoiding economic hardships suffered during the First World War.[112]

Overy states that blitzkrieg as a "coherent military and economic concept has proven a difficult strategy to defend in light of the evidence".[113] Milward's theory was completely contrary to Hitler's and German planners' intentions. It was their fear of the spectre of 1914 that emerged victorious in the conflict of goals between armament in breadth for a short war and armament in depth for a feared long war. The Germans were aware of the error of the First World War, and rejected the concept of orientating its economy geared to fighting only a short war. Hitler proclaimed to rely on surprise alone was "criminal", and that "we have to prepare for a long war along with surprise attack".[114]

During the winter of 1939–40, Hitler decreased the size of the fighting manpower in order to return as many skilled workers to the factories as was possible. It was realised that the war would be decided in the factories, not a quick-decision "Panzer operation".[114]

Throughout the 1930s, Hitler had ordered rearmament programs that cannot be considered limited.[115] In November 1937 Hitler had indicated that most of the armament projects would be completed by 1943–45.[116] The rearmament of the Kriegsmarine was to have been completed in 1949, the Luftwaffe rearmament program was to have been completed in 1942 with a force capable of carrying out strategic bombing using heavy bombers.[117] The construction and training of motorised forces and a full mobilisation of the rail networks would not begin until 1943 and 1944 respectively.[117] Hitler needed to avoid war until these projects were complete. Hitler's misjudgements in 1939 forced him into war before he was able to complete rearmament.[116]

After the war, Albert Speer pointed out that the German economy achieved greater armaments output, not because of diversions of capacity from civilian to military industry, but through streamlining of the economy.[118] Richard Overy pointed out some 23 percent of German output was military by 1939. Between 1937 and 1939 70 percent of investment capital went into rubber, synthetic fuel development, aircraft and shipbuilding industries. Hermann Göring had consistently stated the task of the Four Year Plan was to rearm Germany for total war. Adolf Hitler's correspondence with his economists also reveals that his intent was to wage war in 1943–1945 when the resources of central Europe had been absorbed into the Third Reich.[119]

Living standards were not high in the late 1930s. Consumption of consumer goods had fallen from 71 percent in 1928 to 59 percent in 1938.[120] The demands of the war economy reduced the amount of spending in non-military sectors to satisfy the demand for the armed forces. On 9 September the Head of the Reich Defence Council, Goring called for complete "employment" of living and fighting power of the national economy for the duration of the war.[121] Overy presents this as evidence that a "blitzkrieg economy" did not exist.[122]

Adam Tooze supports Overy. Tooze explains that the German economy was planning for a long war. The expenditure for this war was extensive and put the economy under severe strain. The German leadership were concerned less with how to balance the civilian economy and the needs of civilian consumption, but rather to figure out how to best prepare the economy for total war.[123] Once war had begun, Hitler urged his economic experts to abandon caution and expend all available resources on the war effort. The expansion plans only gradually gained momentum in 1941.[124] Tooze maintained the huge armament plans in the pre-war period did not indicate any clear-sighted blitzkrieg economy or strategy.[125]

There is the argument that the Heer (the German army) itself was not ready for blitzkrieg at the start of the war. The blitzkrieg method called for a young, highly skilled mechanised army. In 1939–40, 45 percent of the army was 40 years old, and 50 percent of all the soldiers had just a few weeks' training.[117] The German Army, contrary to what the blitzkrieg legend suggests, was not fully motorised. The German Army could muster only 120,000 vehicles compared to the 300,000 of the French Army. The British also had an "enviable" contingent of motorised forces.[117] Thus, "the image of the German 'Blitzkrieg' army is a figment of propaganda imagination".[117] During the First World War the German army used horses for logistics, 1.4 million of them, in the Second World War it used 2.7 million horses. Moreover just 10 percent of the Army was motorised in 1940.[117]

Half of the German divisions available in 1940 were combat ready,[117] but often being more poorly equipped than the British and French Armies, as well as the German Army of 1914.[126] In the spring, 1940, the German army was semi-modern.[126] A small number of the best equipped and "elite divisions were offset by many second and third rate divisions".[126] Apart from the few motorised and Panzer Divisions, ninety percent of the German Army was not a blitzkrieg army.[126][127]

It has been argued by John Mosier that, while the French soldiers in 1940 were better trained than German soldiers, as were the Americans later, and the German army was the least mechanised of the major armies, its leadership cadres were both larger and superior and their high standards of leadership were the primary reason for the successes of the German army in World War II as it had been in World War I.[128]

James Corum states a prevalent myth about the Luftwaffe and its blitzkrieg operations is that it had a doctrine of terror bombing, in which civilians were deliberately targeted in order to break the will or aid the collapse of an enemy.[129] After the bombing of Guernica in 1937 and of Rotterdam in 1940, it was commonly assumed that terror bombing was a part of Luftwaffe doctrine. During the interwar period the Luftwaffe leadership rejected the concept of terror bombing, and confined the air arm's use to battlefield support of interdiction operations.[129]

The vital industries and transportation centers that would be targeted for shutdown were valid military targets. Civilians were not to be targeted directly, but the breakdown of production would affect their morale and will to fight. German legal scholars of the 1930s carefully worked out guidelines for what type of bombing was permissible under international law. While direct attacks against civilians were ruled out as "terror bombing", the concept of the attacking the vital war industries- and probable heavy civilian casualties and breakdown of civilian morale-was ruled as acceptable.[130]

Corum continues: GeneralWalther Wever compiled a doctrine known as The Conduct of the Aerial War. This document, which the Luftwaffe adopted, rejected Giulio Douhet's theory of terror bombing. Terror bombing was deemed to be "counter-productive", increasing rather than destroying the enemy's will to resist.[131] Such bombing campaigns were regarded as diversion from the Luftwaffe's main operations; destruction of the enemy armed forces.[132] The bombings of Guernica, Rotterdam and Warsaw were tactical missions in support of military operations and were not intended as strategic terror attacks.[36]

J.P. Harris states that most Luftwaffe leaders from Goering through the general staff believed as did their counterparts in Britain and the United States that strategic bombing was the chief mission of the air force and that given such a role, the Luftwaffe would win the next war and that:

Nearly all lectures concerned the strategic uses of airpower; virtually none discussed tactical co-operation with the Army. Similarly in the military journals, emphasis centred on 'strategic’ bombing. The prestigious Militärwissenschaftliche Rundeschau, the War Ministry's journal, which was founded in 1936, published a number of theoretical pieces on future developments in air warfare. Nearly all discussed the use of strategic airpower, some emphasising that aspect of air warfare to the exclusion of others. One author commented that European military powers were increasingly making the bomber force the heart of their airpower. The manoeuvrability and technical capability of the next generation of bombers would be ’as unstoppable as the flight of a shell.[133]

The Luftwaffe did end up with an air force consisting mainly of relatively short-range aircraft, but this does not prove that the German air force was solely interested in ’tactical’ bombing. It happened because the German aircraft industry lacked the experience to build a long-range bomber fleet quickly, and because Hitler was insistent on the very rapid creation of a numerically large force. It is also significant that Germany's position in the centre of Europe to a large extent obviated the need to make a clear distinction between bombers suitable only for ’tactical’ and those necessary for strategic purposes in the early stages of a likely future war.[134]

British theorists J.F.C. Fuller and Captain B. H. Liddell Hart have often been associated with the development of blitzkrieg, though this is a matter of controversy. In recent years historians have uncovered that Liddell Hart distorted and falsified facts to make it appear as if his ideas were adopted.[135] After the war Liddell Hart imposed his own perceptions, after the event, claiming that the mobile tank warfare practiced by the Wehrmacht was a result of his influence.[135] Blitzkrieg itself is not an official doctrine and historians in recent times have come to the conclusion it did not exist as such:

It was the opposite of a doctrine. Blitzkrieg consisted of an avalanche of actions that were sorted out less by design and more by success. In hindsight—and with some help from Liddell Hart—this torrent of action was squeezed into something it never was: an operational design.[12][13]

By "manipulation and contrivance, Liddell Hart distorted the actual circumstances of the blitzkrieg formation and he obscured its origins. Through his indoctrinated idealization of an ostentatious concept he reinforced the myth of blitzkrieg".[136] By imposing, retrospectively, his own perceptions of mobile warfare upon the shallow concept of blitzkrieg, he "created a theoretical imbroglio that has taken 40 years to unravel."[136] The early 1950s literature transformed blitzkrieg into a historical military doctrine, which carried the signature of Liddell Hart and Heinz Guderian. The main evidence of Liddell Hart's deceit and "tendentious" report of history can be found in his letters to the German Generals Erich von Manstein and Heinz Guderian, as well as relatives and associates of Erwin Rommel. Liddell Hart, in letters to Guderian, "imposed his own fabricated version of blitzkrieg on the latter and compelled him to proclaim it as original formula".[137][138] Historian Kenneth Macksey found Liddell Hart's original letters to Guderian, in the General's papers, requesting that Guderian give him credit for "impressing him" with his ideas of armoured warfare. When Liddell Hart was questioned about this in 1968, and the discrepancy between the English and German editions of Guderian's memoirs, "he gave a conveniently unhelpful though strictly truthful reply. ('There is nothing about the matter in my file of correspondence with Guderian himself except...that I thanked him...for what he said in that additional paragraph'.)".[139]

During World War I, Fuller had been a staff officer attached to the newly developed tank force. He later developed plans for massive, independent tank operations, which he claimed was subsequently studied by the German military. It is variously argued that Fuller's wartime plans and post-war writings were an inspiration, or that his readership was low and German experiences during the war received more attention. The Germans' view of themselves as the losers of the war may be linked to the senior and experienced officers' undertaking a thorough review, studying, and rewriting of all their Army doctrine and training manuals. The UK's response was much weaker.[140]

Both Fuller and Liddell Hart were "outsiders": Liddell Hart was unable to serve as an active soldier because of ill-health, and Fuller's abrasive personality resulted in his premature retirement in 1933. Their views therefore had limited impact within the British Army's official hierarchy. The British War Office did permit the formation of an Experimental Mechanized Force on 1 May 1927, composed of tanks, lorried infantry, self-propelled artillery and motorized engineers, but financial constraints prevented the experiment from being extended.

It has been argued that blitzkrieg was not new. The Germans did not invent something called blitzkrieg in the 1920s and 1930s.[98][141] Rather the German concept of wars of movement and concentrated force were seen in wars of Prussia and the German wars of unification.[98] The first European general to introduce rapid movement, concentrated power and integrated military effort was Swedish King Gustavus Adolphus during the Thirty Years' War. The appearance of the aircraft and tank in the First World War, often hailed as a revolution in military affairs (RMA), offered the German military a chance to get back to the traditional war of movement as practiced by Moltke the Elder.[98] The so-called "blitzkrieg campaigns" of 1939 – circa 1942, were well within that operational context.[98]

At the outbreak of war, the German army had no radically new theory of war named Blitzkrieg or otherwise. The operational thinking of the German army had not changed significantly since the First World War or since the late 19th century. J. P. Harris and Robert M. Citino point out that the Germans had always had a marked preference for short, decisive campaigns – but were unable to achieve short-order victories in First World War conditions. The transformation from the stalemate of the First World War into tremendous initial operational and strategic success in the Second, was partly the employment of a relatively small number of mechanised divisions, most importantly the Panzer divisions, and the support of an exceptionally powerful air force.[142]

Heinz Guderian is widely regarded as being highly influential in developing the military methods of warfare used by Germany's tank men at the start of the Second World War. This style of warfare brought maneuver back to the fore, and placed an emphasis on the offensive. This style, along with the shockingly rapid collapse in the armies that opposed it, came to be branded as blitzkrieg warfare.[31]

Following Germany's military reforms of the 1920s, Heinz Guderian emerged as a strong proponent of mechanized forces. Within the Inspectorate of Transport Troops, Guderian and colleagues performed theoretical and field exercise work. Guderian met with opposition from some in the General Staff, who were distrustful of the new weapons and who continued to view the infantry as the primary weapon of the army. Among them, Guderian claimed, was Chief of the General Staff Ludwig Beck (1935–38), who he alleged was skeptical that armored forces could be decisive. This claim has been disputed by later historians. For example, James Corum stated:

Guderian expressed a hearty contempt for General Ludwig Beck, chief of the General Staff from 1935 to 1938, whom he characterized as hostile to ideas of modern mechanised warfare: [Corum quoting Guderian] "He [Beck] was a paralyzing element wherever he appeared....[S]ignificantly of his way of thought was his much-boosted method of fighting which he called delaying defense". This is a crude caricature of a highly competent general who authored Army Regulation 300 (Troop Leadership) in 1933, the primary tactical manual of the German Army in World War II, and under whose direction the first three panzer divisions were created in 1935, the largest such force in the world of the time.[143]

By Guderian's account he single handedly created the German tactical and operational methodology. Between 1922 and 1928 Guderian wrote a number of articles concerning military movement. As the ideas of making use of the combustible engine in a protected encasement to bring mobility back to warfare developed in the German army, Guderian was a leading proponent of the formations that would be used for this purpose. He was later asked to write an explanatory book, which was titled Achtung Panzer! (1937). In it he explained the theories of the tank men and defended them.

Guderian argued that the tank would be the decisive weapon of the next war. "If the tanks succeed, then victory follows", he wrote. In an article addressed to critics of tank warfare, he wrote "until our critics can produce some new and better method of making a successful land attack other than self-massacre, we shall continue to maintain our beliefs that tanks—properly employed, needless to say—are today the best means available for land attack." Addressing the faster rate at which defenders could reinforce an area than attackers could penetrate it during the First World War, Guderian wrote that "since reserve forces will now be motorized, the building up of new defensive fronts is easier than it used to be; the chances of an offensive based on the timetable of artillery and infantry co-operation are, as a result, even slighter today than they were in the last war." He continued, "We believe that by attacking with tanks we can achieve a higher rate of movement than has been hitherto obtainable, and—what is perhaps even more important—that we can keep moving once a breakthrough has been made."[144] Guderian additionally required that tactical radios be widely used to facilitate co-ordination and command by having one installed in all tanks.

Guderian's leadership was supported, fostered and institutionalized by his supporters in the Reichswehr General Staff system, which worked the Army to greater and greater levels of capability through massive and systematic Movement Warfare war games in the 1930s.

Guderian's book incorporated the work of theorists such as Ludwig Ritter von Eimannsberger, whose major book, The Tank War (Der Kampfwagenkrieg) (1934) gained a wide audience in the German Army.[145] Another German theorist, Ernst Volckheim, wrote a huge amount on tank and combined arms tactics and was influential to German thinking on the use of armoured formations, but his work was not acknowledged in Guderian's writings.[145]

^ abShirer, William, The Collapse of the Third Republic: An Inquiry into the Fall of France in 1940, Ch.29–31, "The Fall of France I, II, (and) III" for a (partially eye-witnessed) account of the strategic and tactical success in the Battle of France

^Willmott 1984, p. 89 Quote: "Many examples of the experiences and losses suffered by German formations moving up to the front are well known. Panzer Lehr, for instance, on 7 June alone lost 84 half-tracks, prime movers and self propelled guns, 40 fuel bowsers, 90 soft-skinned vehicles and five tanks as it made its way from LeMans to Caen."

^Liddell Hart 1970, p. 73, General Georges: "Crediting our enemies with our own procedure we had imagined that they would not attempt the passage of the Meuse until after they had brought up ample artillery. The five or six days necessary for that would have easily given us time to reinforce our own dispositions.".

^Guderian's remarks are from an unnamed article published in the National Union of German Officers, 15 October 1937 as quoted in Panzer Leader, pp.39–46. Italics removed—the quoted sections are all italics in the original.

^Fanning contends that the word was not the invention of western journalists, but existed in different forms in a variety of languages. He asserts it was not used by German military theorists or by the German Army prior to 1939. In the thousands of military journals produced in Germany between 1933 and 1939, the word is mentioned only once in two different papers. In English and other languages apart from German, the phrase had been used since the 1920s.[1]Richard Holmes contends that the word was anglicized and did not enter into popular/widespread usage until used by journalists, when he asserts it was first coined. Holmes asserts there was no "coherent doctrine" or a "unifying concept of blitzkrieg".[this quote needs a citation] Harris notes that it was the British who coined the phrase first, to describe the German successes in Poland. The German popular press did not use the word until later. Heinz Guderian noted that it was a word coined by the Allies; "as a result of the successes of our rapid campaigns our enemies (emphasis added) coined the word 'Blitzkrieg'".[2] Harris concludes, "Blitzkrieg seems to have gained popularity as a piece of journalistic sensationalism – a buzz-word with which to label the spectacular early successes of the Germans in the Second World War. In the West it seems first to have been applied to the Polish campaign of September 1939 and was later attached to the Norwegian and Western campaigns of 1940, to the Balkan campaign of 1941, to some of the North African campaigns, and to the early stages of the attack on Russia, but most enduringly to the bombing campaign against Great Britain (especially London), which is still popularly known as the ’Blitz’."[3] German historian Karl-Heinz Frieser disputes that the word was established through British journalism. He points to the word and its mention in two articles prior to 1939. However, he does accept the word only gained publicity through journalism. He notes that the British press were first to do this on 25 September 1939, but also points to the extensive use of the word by the German press in 1940 after the fall of France some nine months later.[4][5]

^Some of the historians that have disputed the originality and formalization of the blitzkrieg are: Shimon Naveh,[12] John Paret,[13]Karl-Heinz Frieser,[14] Richard Overy,[15] Mungo Melvin,[16] Steven Mercatante,[17] David Glantz,[18] etc.

^Many notable historians still use the term blitzkrieg to describe several Wehrmacht military operations that were spearheaded by a dense concentration of armoured and motorized formations with the aim of delivering a breakthrough, and exploiting it with speed to paralyze and encircle the enemy. Some of the historians that still use the term to describe such Wehrmacht military operations are: David Glantz,[6][21][22][23] Jonathan House,[24] Lloyd Clark,[25] Antony Beevor,[26][27] Mungo Melvin,[28]John Erickson,[29] Steven Mercatante,[30] etc.

^Heinz Guderian is popularly alleged to be one of the founders of the blitzkrieg idea[31]

^Nothing appeared in Luftwaffe 'doctrine' stipulating "terror" as a major operational factor. The method of "terror", was denied to German aerial operations (and strategic bombing methods) by the Luftwaffe field manual The Conduct of Air Operations, Regulation 16, issued in 1935. James Corum covers the subject in The Roots of Blitzkrieg: Hans von Seeckt and German Military Reform[34] In other work, The Luftwaffe: Creating the Operational Air War, 1918–1940, Corum goes into greater detail. Regulation 16 denied "terror" operations against civilians.[35] Corum does state that it was not until 1942 when indiscriminate "terror" operations, in which terror and civilian casualties become the primary target, took place.[36]

^As far as the Ju 87 is concerned, it is thought the sirens were suggested to the Junkers company by Ernst Udet to undermine the morale of enemy forces[37]

Falls, Cyril; A. F. Becke (maps) (1930). Military Operations Egypt & Palestine from June 1917 to the End of the War. Official History of the Great War Based on Official Documents by Direction of the Historical Section of the Committee of Imperial Defence. 2 Part II. London: H.M. Stationery Office. OCLC256950972.Cite uses deprecated parameter |coauthor= (help)

Fanning, William, Jr. (April 1997). "The Origin of the term "Blitzkrieg": Another view". Journal of Military History61 (2): 283–302. doi:10.2307/2953968.